The difference between lagers and IPAs lies in several key factors: the brewing process, the yeast used, the fermentation temperature, the ingredients, and the hop bitterness.
1. Brewing Process:
Lagers and IPAs are brewed using different methods. Lagers undergo a process called “bottom fermentation,” where the yeast settles at the bottom of the fermentation vessel. This results in a clean and crisp taste. On the other hand, IPAs are typically brewed using “top fermentation,” where the yeast ferments at the top of the vessel, resulting in more fruity and aromatic flavors.
2. Yeast:
The type of yeast used in brewing also contributes to the differences between lagers and IPAs. Lagers are made with bottom-fermenting yeast, usually a strain of Saccharomyces pastorianus. This yeast ferments at cooler temperatures (around 45-55°F or 7-13°C) and produces fewer esters, resulting in a cleaner taste. IPAs, on the other hand, are often brewed with top-fermenting yeast, typically strains of Saccharomyces cerevisiae. These yeasts ferment at warmer temperatures (around 60-70°F or 15-21°C) and produce more fruity and spicy flavors.
3. Fermentation Temperature:
The fermentation temperature also plays a role in the difference between lagers and IPAs. Lagers are fermented at cooler temperatures, which slows down the fermentation process and allows for a longer and more gradual fermentation. This results in a smoother and more refined flavor profile. IPAs, on the other hand, are typically fermented at warmer temperatures, which speeds up the fermentation process and can produce more robust and bold flavors.
4. Ingredients:
The ingredients used in lagers and IPAs also contribute to their distinct characteristics. Lagers are typically brewed with lighter malts, such as Pilsner malt, which imparts a lighter color and a more delicate flavor. IPAs, on the other hand, often use a variety of malts, including pale malt, caramel malt, or even specialty malts like roasted barley, which can provide a richer and more complex flavor profile.
5. Hop Bitterness:
The amount of hop bitterness is a significant differentiator between lagers and IPAs. IPAs are known for their high hop bitterness, often exceeding 40 International Bitterness Units (IBU) and commonly reaching over 60 IBU. This bitterness comes from the hops used during the brewing process and contributes to the distinctively bitter and hop-forward taste of IPAs. In contrast, lagers are typically more subtly hopped, with bitterness ranging from around 20-40 IBU. This milder hop presence allows other flavors, such as malt sweetness, to shine through in lagers.
To summarize:
Lagers are brewed through a bottom fermentation process, using bottom-fermenting yeast and cooler fermentation temperatures. They typically have a cleaner taste, lighter malts, and milder hop bitterness.
IPAs, on the other hand, are brewed with top fermentation, top-fermenting yeast, and warmer fermentation temperatures. They often feature a more pronounced hop bitterness, a variety of malts, and a range of fruity and spicy flavors.
It's important to note that these are general differences, and there can be variations within each style. Brewers often experiment with different techniques and ingredients, resulting in a wide array of lagers and IPAs available in the market. So, whether you prefer the crispness of a lager or the hoppy intensity of an IPA, there's a beer out there to suit your taste preferences.